LLD User Macros are expanded already in quite a few places ... but not in other:
https://www.zabbix.com/documentation/2.0/manual/appendix/macros/supported_by_location#macros_used_in_low-level_discovery

In some situations it would be very useful, if LLD User Macros could also be expanded in the description part of ITEMs and TRIGGERs (just like its already possible in ITEM.NAME and TRIGGER.NAME).

Background: I would like to use this to pass some LLD specific informations to the messages sent/used by operations in the actions. At the moment I need to parse this out - complicated - from the name (which contains more text - for usability - than needed by the media script of the operation).